public class Test {
    public static void main(String[] args) {
        LinkedList list=new LinkedList();
        list.addFirst(1);
        list.addFirst(2);
        list.addFirst(1);
        list.addFirst(4);
        list.addLast(1);
        list.addIndex(3,99);
        list.removeAll(1);
        list.display();

    }
}
